A silicate of magnesium and iron, Green to yellow-green, rarely brown. Sometimes higher. Birefringence is high (0.036), and careful orientation is needed to produce the finest faceted stones.

Peridot is a well-known and ancient gemstone, with jewelry pieces dating all the way back to the Pharaohs in Egypt. The gem variety of the mineral Olivine, it makes a lovely light green to olive-green gemstone.

The intensity of color depends on the amount of iron present in a Peridot's chemical structure; the more iron it contains the deeper green it will be. The most desirable color of Peridot is deep olive-green with a slight yellowish tint. Deeper olive-green tones tend to be more valuable than lighter colored greens and yellowish-greens.